1. Field of the Invention
The present invention relates to a decal for manufacturing a multi-colored retroreflective sticker having a variety of colorful letters or patterns and, more particularly, to a decal for manufacturing a multi-colored retroreflective sticker, which has high brightness and saturation under natural light.
2. Description of the Related Art
A variety of colored retroreflective decals have been developed to date and are utilized for the manufacture of bands or stickers that are attached to various personal items such as clothes, shoes, bags, etc. As such, these bands or stickers may exhibit retroreflective characteristics upon artificial light irradiation, especially upon irradiation with an artificial light source such as a lighting lamp or headlamp, thus increasing the ability of a person to discriminate objects with such bands or stickers at nighttime, thereby preventing traffic accidents or safety accidents. Further, these bands or stickers have been used for advertisements, brands and labels of corresponding items, or decorative effects thereof. The colored retroreflective decals are provided in diverse forms configured such that a sheet having a reflective layer formed mainly of a metal such as aluminum or silver by a deposition process is subjected to a predetermined cutting process to give final products such as bands or stickers having letters or patterns. These products are attached to personal items to thus manifest retroreflective characteristics upon irradiation with an artificial light ray. As such, final products, for example, colored retroreflective bands or stickers, are researched for only luminance thereof with reflection to a silvery white color by an artificial light source, without taking into consideration the color appearance under natural light.
Although the colored retroreflective decals have high luminance upon irradiation with an artificial light source, brightness of colorful letters or patterns of bands or stickers as final products using the decals may decrease under natural light, undesirably deteriorating color appearance.
More specifically, the decal for a colored retroreflective band or sticker as a final product is configured such that a color layer, a reflective layer, and a bonding layer, and optionally, a non-thermal or thermal adhesive layer, as necessary, are sequentially formed on the rear side of a glass bead layer. As such, the color layer shows the background color of the decal.
The reflective layer provided on the color layer that shows the background color of the decal is made of a metal that shows dark grey having low brightness, such as aluminum or silver, so that brightness of the color layer may decrease, undesirably deteriorating color appearance.
Therefore, the colored retroreflective decals manifest poor color appearance under natural light, thus lowering the quality of products. Furthermore, when the bands or stickers manufactured using such decals having poor color appearance are attached to personal items, the decorative effect and quality of the items may also decrease.
Also, the color layer, which is provided on the rear side of the glass bead layer of the colored retroreflective decal, has a single color to thus show the background color of the sheet for a decal, and also merely functions to give a colored decal under natural light.
Since the color layer is provided on the rear side of the glass bead layer in the reflective structure, saturation of the color layer may also decrease under natural light.
Recently, development of decals for manufacturing multi-colored stickers having relatively high brightness under a natural light source is required. Specifically, there is a need for decals configured to include a multi-colored printing layer having a variety of colorful letters or patterns on the glass bead layer, and to achieve complementary color contrast that increases brightness of the multi-colored printing layer by the background color of the decal and simultaneously to ensure high-quality products by increasing saturation thereof.